Safety device for elevators.



No. 687,|87. Patented Nov. 26, |90I. U. S. ALZ &. A..H. HUENISCH.

SAFETY DEVICE FOB ELEVATURS.

(Application led Feb. 8, 1901.)

(No Model.) v

UNITED STAfrEs 'PATENT OFFICE.

URBAN S. ALZ, OF GARDENVILLE, AND AUGUST H. HOENISOH, OF BALTIMORE, MARYLAND, ASSIGNORS,n BY DIRECT AND MESNE ASSIGNMENTS, TO FREDERICK DENI-IARD, OF BALTIMORE, MARYLAND.

SFETYA DEVICE `FOR ELEVATORS'.

SPECIFICATION forming part of Letters Patent N o. 687,187, dated November 26, 1901.

Application filed February 8, 1901. Serial No. 46.528. (No model.)

.To all whom, it may concern:

Be it known that we, URBAN S. ALZ, of Gardenville, Baltimore county, and AUGUST H. HOENISCH, of Baltimore, State of Maryland,

haveinventedcertainImprovementsinSafety Devices for Elevators, of which the following is a specification.

This invention relates to automatic devices for preventing a too-rapid descent of an ele- Io vator-car, being more especially adapted for the purpose of arresting the downward movement of the carin case of accident to the hoisting and lowering mechanism.

The present invention is an improvement upon what is set forth in the patentto Urban S. Alz, dated July 4, 1899, and numbered 628,260. Y

The objects of this invention are to simplify the construction and arrangement of parts,

zo produce a more compact structure, and insure a more positive and effective operation of the working air-cushions.

The invention consists in the particular construction and combination of parts, all as will be hereinafter fully described, and specifically set forth in the appended claims.

In the accompanying drawings, which form a part of this specification, and -in which like letters of reference indicate like parts 3o throughout the several views, Figure l is a vertical sectional view illustrating the application of the invention to an elevator-car. Fig. 2 is a side elevation on an enlarged scale. Fig. 3 is a plan view, the upper floor or horizontal partitionbeing removed. Fig. Il is a detail sectional view of the air-chamber into which the cylinders exhaust. Fig. 5 is a detail sectional view of one of the air-cylinders.

Referring to said drawings, A A designate 4o the corner-posts of the elevator-shaft, and A the vertical T-rails, which serve to guide the carin the shaft. The elevator-shaft is also provided with L. -shaped guide rails B B, which gradually converge, as shown, to the bottom of the shaft, the said guide-rails operating the pistons of the cylinders by engaging the slide-bars, hereinafter described.

Beneath the floor of the car are arranged horizontal partitions or ioors c, c', and c2,

which support the devices hereinafter described. Disposed between the partitions c and c' are two air-cylinders D D, the pistons of which are connected by rods d to a transverse slide-bar E, the latter working between said partitions. `The cylinders vD D are opposite to a corresponding pair of cylinders F t F, located between the floors c and c2 and having their piston-rods connected to a transverse slide-bar G, working between said partitions. The slide-bars E and Gare guided by the inclined guide-rails B, and to this end the inner flange h of the shoes, said flange is somewhat thicker than the other flange h', for it will be noted that the said thicker flange bears againstthe rail when the car is descending.

I designates an air-chamber to which the j four cylinders are connected, the cylinders D being connected by short pipes d', while the cylinders F are connected to said air-chamber by pipes f, extending from the rear ends thereof upward and along the partition c, being bent downward, as shownin Fig. l, to enter the bottom of the cylinder. The ends of the pipes d and f are normally closed by clap-valves m, which permit theair to enter the chamber from any or all of the cylinders, but prevent back pressure. By this arrangement the air from the cylinders may be forced into the air-chamber when. the elevatorcar is descending, 'but cannot return. Therefore should any of the cylinders become broken or accidentally injured th'e air in the other cylinders could not find an outlet therethrough. Each cylinderis therebyindependently connected to the air-chamber, and an injury to one will not affect the operation of the others. It will also be noted that the pipes leading from the several cylindersinto the air-chamber are comparatively small and that therefore the compression of air in the cylinders by a sudden descent of the elevator-car will be effective in arresting the descent. The pistons in the cylinders are simi lar to those employed in connection with an ordinary bicycle-pump, carrying a dished leather washer, so that air is drawn into the cylinders around the Washers upon an outward movement ofthe piston and compressed in the cylinders upon a rearward movement of said piston, the compression of the air in the cylinders and air-chamber acting as a cushion to gradually stop the car. In casca car is stopped between floors of a building the operator can lower the car to the desired extent by exhausting air from the chamber I, and for this purpose said chamber is connected bya pipe n to a valve-chamberNand said valve-chamber provided with a Valve, the stem 0 of which is operated by a cranklever O, the vertical portion or presser-rod of which passes upward through the iioor of the car at a point convenient to the operator and out of the Way of accidental operation. It will be understood that before the descent of the car the outlet-valve of the air-chamber is opened to relieve the pressure and then closed, so that the gradual compression of air as the car descends at a normal rate of speed will not be confined in the cylinders, but will enter said air-chamber also, and that in case of a sudden descent of the car due to an accident or other cause the car would gradually come to a stop when the pressure of air is equalized in the cylinders and air-chamber.

From the foregoing description, in con nection with the accompanying drawings, the construction and operation of our improved devices will be readily understood, and it will be noted that by means of the improved construction and arrangement of parts a direct connection is madel between the cylin-- ders and slide-bars, that the cylinders are all connected independently to an air-chamber, and that pressure in said air-.chamber may be relieved; also, that L-rails are employed to guide the slide-bars.

Having thus described our invention, what We claim as new, and desire to secure by Letters Patent, is

l. In a safety device for elevators, the combination with the car having the horizontal partitions or supports, cylinders arranged between said partitions at opposite sides of the car, slide-bars having a movement between the partitions in the same plane with said cylinders and to 'which the piston-rods of the cylinders are directly connected, and grooved shoes connected to the ends of said slidebars; together with the inclined guide-rails each having an inwardly-projecting flange which engages the grooved shoes, substantially as shown and for the purpose set forth.

2. In a safety device for elevators, the combination with the car, of cylinders supported below the car at opposite sides thereof in different horizontal planes, slide-bars connected to the piston-rods of said cylinders, and inclined guide-rails with which said slide-bars engage; together with an air-chamber, pipes of small diameter connecting the cylinders to said air-cham ber, and valves preventing back pressure in said pipes, substantially as shown and for the purpose set forth.

3. In a safety device for elevators, the combination with the car, of air-cylinders supported therein, slide-bars connected to the pistou-rods of said cylinders, and inclined guide-rails with which said slide-bars engage; together with an air-chamber, pipes of small diameter connecting the cylinders to said airchamber, valves at the ends of said pipes, a valve-chamber connected to said air-chamber, a valve in the valve-chamber, and a cranklever operating said valve, substantially as shown and for the purpose set forth.

URBAN S. ALZ. AUGUST H. IIOENISCII.

In presence of- J. A. I-IILLEARY, J r., AUGUSTUS M. DENHARD. 

